A fast and quantitative assay for developing zeolite-type hydrocarbon trap catalyst

A fast parallel method for determining the amount of toluene adsorbed over a variety of zeolites has been established. A three-step approach, including parallel adsorption of toluene onto the catalyst samples, the destructive or non-destructive extraction of trapped toluene by solvents including n-octane and 2,2,4,-trimethyl pentane (TMP) with NaOH and HF, respectively, and optical assay based on the characteristic absorption of toluene (ca. 261 nm of UV), has been performed sequentially to give a fast parallel and quantitative evaluation of the amount of toluene trapped over promising zeolite-type hydrocarbon trap catalysts. The results correlate well with those obtained by means of traditional, time-consuming techniques such as temperature-programmed desorption (TPD).